Mayor de Blasio announced new rules Sunday to boost crane safety following Friday’s deadly collapse in Tribeca — as the man killed in the horror was eulogized by his shattered widow.

Starting Monday, crawler cranes like the one that toppled onto Worth Street will have to be shut down and put into “safety mode” whenever steady winds are forecast to exceed 20 mph or gusts to exceed 30 mph, de Blasio said.

Previously, the rules went into effect at 30 mph and 45 mph, respectively, or according to manufacturers’ recommendations.

“We want the action taken the day before if we have indication of a higher wind level,” de Blasio said.

The city will also “increase enforcement of sidewalk and street closures” and require operators to notify nearby residents and businesses before moving a crane.

An official probe of Friday’s incident is underway but will likely take “several months” to complete, the mayor added.

The crane collapsed while being lowered due to high winds, and city Buildings Commissioner Rick Chandler said it wasn’t yet clear whether extending the crane’s boom to its maximum, 565-foot length the day before was a factor.

Meanwhile, the grieving widow of victim David Wichs, who was killed while walking to work, told hundreds of mourners at his funeral that she was struggling with the loss.

“I am devastated that I have to live the rest of my life without you,” Rebecca Guttman said from the pulpit of Congregation Kehilath Jeshurun on the Upper East Side. “But even though the feeling right now is unbearable, I want you to know that I will do my best to live for us both.”

Wichs, 38, lived out the American dream, graduating from Harvard University after immigrating from the former czechoslovakia at age 14, and working at Tower Research Capital, a computerized stock-trading firm in Tribeca.

Rabbi Emeritus Haskel Lookstein said Wichs donated “an unusually large part of his income” to charity, but also “gave of his person to everybody sitting here.”